Long-lived superheavy particles in dynamical supersymmetry-breaking models in supergravity

Superheavy particles of mass similar or equal to 10(13)-10(14) GeV with a lifetime similar or equal to 10(10)-10(22) yr very interesting, since their decays may account for the ultrahigh energy (UHE) cosmic rays discovered beyond the Greisen-Zatsepin-Kuzmin cutoff energy E similar to 5 x 10(10) GeV. We show that the presence of such long-lived superheavy particles is a generic prediction of QCD-like SU(N-c) gauge theories with N-f flavors of quarks and antiquarks and a large number of colors N-c. We construct explicit models based on supersymmetric SU(N-c) gauge theories and show that if the dynamical scale Lambda similar or equal to 10(13)-10(14) GeV and N-c=6-10 the lightest composite baryons have the desired masses and lifetimes to explain the UHE cosmic rays. It is interesting that in these models the gaugino condensation necessarily occurs and hence these models may play the role of the so-called hidden sector for supersymmetry breaking in supergravity. [S0556-2821(99)04722-0].